The present invention relates to the field of wire pullers, and more particularly to fish tape devices used for pulling electrically insulated wires or other materials through a conduit. Further, the present invention relates to attachments to fish tape devices to aid in pulling the wires through a conduit.
It has long been known in the residential, commercial, and industrial electrical contracting fields to provide electrical circuits comprising junction boxes, switches, and outlets interconnected by a series of electrically insulated wires routed through lengths of conduit or piping. In many cases, it is necessary to draw the insulated wires through the lengths of conduit over relatively great distances, or behind walls, or past bends in the conduit. Where the insulated wires are not sufficiently rigid such that they cannot be drawn through the conduit by feeding the wires themselves through the conduit, a device known in the art as a xe2x80x9cfish tapexe2x80x9d may be used for drawing the wires or a string attached to the wires through the conduit.
A fish tape generally comprises a thin yet resilient strip or rod of metal or plastic having a loop or other attachment on one end. The fish tape can be fed into one end of the conduit and is capable of following bends in the conduit without hindrance. After the fish tape has been drawn through the conduit such that the loop end of the fish tape emerges from an opposite end of the conduit, an insulated wire or string is connected to the loop end of the fish tape and drawn back through the conduit. If a string is connected to the loop end of the fish tape, the string is first drawn through the conduit followed by the wire, which is connected to the other end of the string.
Early fish tapes were loose and uncontained, which often resulted in tangled and knotted fish tape strewn about the floor of the workplace. Modern fish tapes devices, however, often incorporate a reel such that the fish tape is wound around the reel by manually rotating the reel about a handle. More specifically, the reel is formed as a flattened ring-shaped rotatable body having a slot formed all the way around its outer circumference. The reel is usually formed in two generally mirror-image halves that fit together so as to create an interior space for storing the fish tape. The reel has an inner hub on which the fish tape is wound. The free end of the fish tape having the loop attachment extends through the outer slot in the reel. The handle is attached to the reel to facilitate grasping the device while the fish tape is extended and reeled in. As stated above, the reel can rotate relative to the handle to pay out or reel in the fish tape. This is accomplished by positioning the handle to engage the outer slot such that the handle can slide along the slot. In both the early and modem cases described above, however, the fish tape is drawn through the conduit by hand, either by pulling the fish tape itself, or by grasping the reel and turning it to wind the fish tape onto the reel.
One problem with current fish tape devices is that it is very difficult to pull lengthy amounts of wire or string through the conduit. In particular, on long runs of conduit such as often found in a commercial building, several electricians or other workers may be required to manually pull the wire or string through the conduit. Such a procedure is often inefficient, fatiguing, and potentially dangerous. To compound the problem, conventional manually-operated fish tape devices require that the fish tape then be wound about the reel, which wastes valuable time and energy of the electrician.
To address the above-mentioned problems, powered fish tape devices have been developed in which the fish tape is stored within the confines of the device and controllably payed out and reeled in by a drive motor so that the fish tape travels through the conduit until it extends from the free end thereof, where a wire is attached to the end of the fish tape and then drawn through the conduit by reeling the fish tape back into the device. Such a device is disclosed in U.S. Pat. No. 4,917,362. Powered fish tape devices, however, typically include a high number of parts and a sophisticated series of gears, both of which involve high complexity and cost. Furthermore, these devices typically employ their own integrated motors, thus having no adaptability or interoperability with existing fish tape devices.
Still other devices have been developed that address the above-mentioned problems by providing an attachment for existing fish tape devices that enable a user to manually reel the fish tape into the fish tape device. For example, U.S. Pat. No. 5,558,613 discloses a fish tape reel attachment having a rigid frame member comprising two parallel bars that extend along the sides of the fish tape reel and a fixed handle at one end of the frame. A ratchet and/or hand crank is attached to an internal hub disposed between the parallel bars and fitted to the fish tape reel for paying out or reeling in the fish tape. However, the attachment also includes a high number of parts and a series of gears, thus involving high complexity. The attachment would also make the fish tape device awkward to use, because the location of the handle requires the user to support the weight of the device that is cantilevered forward from the handle. Furthermore, the attachment described in U.S. Pat. No. 5,558,613 provides a device for manually reeling in the fish tape, thus resulting in a long and tiring process.
Thus, there is a need for a fish tape device which can reel in a fish tape without manually operating the device. More specifically, there is a need for a fish tape device having low complexity and cost that allows a fish tape to be wound automatically to save valuable time and effort on the part of the user.
These and other needs are provided, according to the present invention, by a fish tape device having a reel center drive device that provides a drive fitting for engaging a driver, such as a powered driver, for automatically reeling in the fish tape about the reel.
In one embodiment, the fish tape reel center drive device of the present invention comprises an attachment for a fish tape reel that is secured in a central opening of the reel using an interference or frictional fit. The body portion of the attachment can be solid and shaped to generally match the shape of the central opening in the reel, but can also take on other forms, such as a hub and spoke configuration, where the spokes extend towards the reel and secure the center drive device as described above. In another embodiment, the center drive device is formed integrally with the reel, such as by injection-molding the reel and the body portion of the center drive device as a one-piece construction. Advantageously, the center drive device includes at least one drive fitting attached to the body portion and positioned coaxially with the central rotation axis of the reel. The drive fitting extends outwardly from the body portion and is positioned for engagement with a powered driver capable of rotating the body portion and, thus, the reel while the handle is held by an operator. Alternatively, drive fittings may be attached to both of the opposite sides of the body portion so that a powered driver can be used on either side of the attachment for automatically reeling in the fish tape.
The fish tape device preferably has a reel that defines a slot extending about its outer circumference and a handle slidably engaged in the slot so that the handle can be grasped in a comfortable position with one hand while the other hand holds a powered driver in engagement with the center drive device to rotate the reel.
The present invention thus seeks to provide a device for easily and efficiently operating a fish tape reel that includes minimal parts. The invention in some embodiments also seeks to provide adaptability and interchangeability with existing fish tape reel devices and powered drivers in the marketplace. As such, the present invention provides a low-cost solution to the problem of automatically reeling in fish tapes.